FIRST REPORT® CONFERENCE COVERAGE

Substituting Liraglutide for Sitagliptin Is Effective in Patients with Type 2 Diabetes

A randomized trial that switched patients with type 2 diabetes from sitagliptin to liraglutide observed improved glycemic control and weight loss after 26 weeks. In addition, the percentage of patients achieving the ADA’s target glycated hemoglobin A1c (HbA1c) level of <7% increased from 30% to 50%. Both drugs are approved by the FDA as treatments for type 2 diabetes. Trial data were presented at the ADA meeting in a poster titled Switching From the DPP-4 Inhibitor Sitagliptin to the Human GLP-1 Analog Liraglutide Further Improves Glycemic Control and Weight Loss in Patients With Type 2 Diabetes.

The 26-week study was an extension of a 52-week randomized, parallel-group, open-label trial that had compared 1.2- and 1.8-mg doses of liraglutide with a 100-mg dose of sitagliptin in patients with type 2 diabetes. The oral drugs were administered daily in combination with metformin. The liraglutide groups experienced a significantly greater reduction in levels of HbA1c and fasting plasma glucose and lost significantly more weight.

Eligible persons were 18 to 80 years of age, with an HbA1c level between 7.5% and 10.0%. Their body mass index had to be ≤45 kg/m2 and they had to have been taking at least 1500 mg of metformin daily for ≥3 months.

A total of 436 patients completed the initial 52-week trial, and 419 continued on to the 26-week extension phase. In total, 381 persons completed all 78 weeks of the study.

In the extension phase, patients who had been in the sitagliptin group were switched to a 1.2- or 1.8-mg dose of liraglutide. Patients who switched to the 1.2 mg-dose of liraglutide experienced a mean decrease of 0.24% in HbA1c levels (P = .006), while patients who switched to 1.8 mg of liraglutide had a mean decrease of 0.45% (P = .0001).

Of the patients who switched to 1.2-mg liraglutide for the study’s extension phase, 29.5% had achieved an HbA1c level <7% at the end of the main phase. This increased to 49.2% of patients at the conclusion of the extension study. The fasting plasma glucose level for this contingent of patients decreased a mean of 0.84 mmol/L from week 52 to week 78 (P = .0004)

Among patients who switched to 1.8 mg of liraglutide, 29.5% had an HbA1c level <7% at 52 weeks versus 50% of patients at 78 weeks. Fasting plasma glucose levels fell a mean of 1.42 mmol/L from
week 52 to week 78 for those who switched to 1.8 mg of liraglutide (P < .0001).

Both groups experienced a statistically significant decrease in mean body weight. Patients who switched to 1.2 mg of liraglutide lost a mean of 1.64 kg (P <.0001), and those who switched to 1.8 mg of liraglutide lost a mean of 2.48 kg (P <.0001).

Patient satisfaction was assessed by comparing Diabetes Treatment Satisfaction Questionnaire scores from week 52 to week 78. The scores increased from a mean of 31.9 to 33.3 for patients who switched to 1.2 mg of liraglutide and from 30.9 to 31.7 for patients who switched to 1.8 mg of liraglutide, which was not significant.

Serious adverse events occurred in 6.0% of patients who switched to 1.2 mg of liraglutide and 2.9% of patients who switched to 1.8 mg of the drug. Gastrointestinal disorders were the most common adverse event, occurring in >30% of patients.